1. Field of the Invention
The present invention relates to an image forming apparatus, such as an electronic copying machine.
2. Description of the Related Art
Generally, the body of an electronic copying machine is provided at its upper portion with a platen glass on which documents are placed. Arranged within the body itself is an image forming mechanism including a photosensitive drum which serves as the image carrier, an optical system for scanning documents with light and forming electrostatic latent images on the photosensitive drum in responsive to light reflected from the documents, a fixing device for fixing the images on sheets of paper, and the like. Among the components of the forming mechanism, the light source of the optical system and the fixing means become hot in particular. This makes it necessary for these elements to be cooled, and it is desirable that the photosensitive drum also be cooled to prevent it from being damaged by excessive heating.
For this purpose, a cooling fan is provided at that end portion of the apparatus body, which is adjacent to the light source and the fixing device, and draws air into the body through intake openings formed in the side thereof and discharges the air through discharge openings formed in the opposite side, thereby cooling components in the body, such as the light source, the fixing devices, and the photosensitive drum.
In the copying machine having the above-described arrangement, however, air is drawn into the body by using a single cooling fan arranged on one side of the body. Therefore, cooling efficiency is low and it is difficult to sufficiently cool the photosensitive drum. When the rotating speed of the fan is increased or a large fan is used so as to improve the cooling efficiency, noise becomes high and the economy of the machine is lowered.